Etiology and Clinical Presentation of Astigmatism
نویسنده
چکیده
In astigmatism variations in the curvature of the cornea or lens along different meridians prevent the light rays from focusing onto a single point. Corneal refraction depends on the corneal curvature. If the cornea is more curved, the power of refraction is higher and vice versa. Corneal and lenticular astigmatism can complement or cancel each other. Their summation represents the so called “total astigmatism”.
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تاریخ انتشار 2012